The advent of virtualization technologies for computing resources has provided benefits with respect to managing large-scale computing resources for many customers with diverse needs and has allowed various computing resources or computing services to be efficiently and securely shared by multiple customers. For example, virtualization technologies may allow a physical server computer to be shared among multiple customers by providing each customer with one or more computing instances hosted by the physical server computer using a hypervisor or virtual machine manager. Each computing instance may be a guest machine acting as a distinct logical computing system that provides a customer with the perception that the customer is the sole operator and administrator of a given computing system.
Paravirtualization allows a computing instance to interact with virtualized hardware utilized by the computing instance (e.g., through making a call to the hypervisor). For example, paravirtualization may provide a computing instance with a software interface to a virtualized hardware device, such as a virtual network or virtual data store, which allows the computing instance to access the virtualized hardware device. A machine image used to launch a computing instance may include drivers for virtualized resources that are attached to the computing instance when the computing instance is launched. In launching the computing instance on a physical host using the machine image, a driver included in the machine image may be loaded on the computing instance and the computing instance may then access an associated virtualized resource available via the physical host.